Differentiating between dengue fever and rash fever

Dengue fever is rapidly increasing in most provinces and cities across the country. Meanwhile, at this time, rash fever is also appearing. How can we differentiate between the two?

Pathogen

Rash fever encompasses various diseases and pathogens, but generally involves fever and a rash. In Vietnam, the most common rash fevers are measles (caused by the measles virus), rubella (caused by the rubella virus), and diseases caused by Rickettsia, with scrub typhus being the most prevalent. Measles and rubella are transmitted through the respiratory tract, while scrub typhus is transmitted by red mites.

Dengue fever is caused by the Dengue virus and is transmitted from infected individuals to healthy individuals who lack immunity against the virus via mosquitoes. Two species of mosquitoes transmit dengue fever: the Aedes aegypti and the Asian tiger mosquito.

Recognizing dengue fever and rash.

Dengue fever is a dangerous epidemic disease. The more mosquitoes that transmit the disease, the faster it spreads, especially if people lack immunity against it. If dengue fever, particularly in children, is not detected and treated promptly, it can lead to many dangerous complications, even death.

Dengue fever typically presents with a persistent high fever for 3-4 days, cough, runny nose, body aches, eye pain, vomiting, and possibly diarrhea. Fever in dengue fever is difficult to reduce with paracetamol during the first 3 days, and when the fever begins to subside, bleeding starts, manifesting as congested skin (redness, dry, bright red lips... due to blood concentration), petechiae (small hemorrhagic spots under the skin), bleeding gums or nosebleeds, red eyes, and often accompanied by vomiting and cold extremities.

Typically, the disease worsens from the third day, especially in children. Therefore, if not diagnosed early and treated promptly, there is a risk of complications such as shock or damage to other organs.

Petechiae (small hemorrhagic spots) under the skin are a symptom of dengue fever.

In cases of scarlet fever, most begin with intermittent high fever (body temperature may rise to 39-40°C) and symptoms such as cough, sore throat, runny or stuffy nose, fatigue, possibly vomiting, and a red rash. Lymph nodes in the head, face, and neck area are often swollen and painful, and may be visible or palpable. The conjunctiva of the eyes may be red, inflamed, and watery. If the cause of the fever is a gastrointestinal virus, digestive disorders may appear soon (loose, mucous stools, no blood, and possibly vomiting after eating). In most cases of scarlet fever, from the 4th day onwards, the patient usually recovers from the fever, regains appetite, and the rash may last for 3-5 days before disappearing.

To differentiate dengue fever from a rash, the simplest method is to stretch the skin with the thumb and index finger of the same hand to reveal the red spots (erythema) or congested area. If the red spots disappear and the redness returns immediately upon release, it's a rash. If the spots remain or the redness reappears after 2 seconds, it's dengue fever (this is the finger pressure or skin color recovery time sign in diagnosing dengue fever). Two criteria to consider dengue fever are sudden high fever and bleeding. If possible, a complete blood count should be performed, which may show a decrease in white blood cells, a significant decrease in platelets, and an increased erythrocyte sedimentation rate (ESR).

What precautions should be taken when suffering from dengue fever?

It's not advisable to assume that having dengue fever once means you won't get it again, because in our country there are four different serotypes of dengue fever. While you might not get one serotype the next time you contract it, you could still get one of the other three.

When treating dengue fever, extreme caution should be exercised when using fever-reducing medication. Only use pure paracetamol (without other combinations), and avoid aspirin, Efferalgan, etc. The best approach is to apply cool compresses to the forehead, armpits, and groin to lower the fever. Even with pure paracetamol, close monitoring is crucial because after a few days of high fever, body temperature may begin to drop, and continued use of fever-reducing medication can be dangerous for the patient.

Some authors advise against administering intravenous fluids immediately during high fever in dengue fever patients, as it can easily lead to shock (especially with protein) due to the body's strong reaction (high fever) against the virus. It is best to replenish fluids and electrolytes lost due to high fever using oral rehydration solution (ORS), but it must be prepared according to instructions (one 5.63g packet of orange-flavored ORS in 200ml of cooled boiled water). In addition, drink plenty of fresh orange juice, lemon juice, and other fruit juices (watermelon, etc.).

If you notice any unusual signs, take the patient to the hospital immediately, especially children (cold hands and feet, cold and clammy skin, restlessness, irritability, abdominal pain, weak pulse, decreased urination, low or fluctuating blood pressure).

According to Zing.vn